Method and apparatus for constructing convertible top linkages



Jan. 20, 1970 R. J. ALLDS 3,490,120

METHOD AND APPARATUS FOR CONSTRUCTING CONVERTIBLE TOP LINKAGES Filed May 15, 1967 3 Sheets-Sheet 1 a W FIG.1.

FIG.2.

INVENTOR RAYMOND J. ALL D5 J ,JW

wwww/ ATTORNEYS Jan. 20, 1970 R. J. ALLDS 3,490,120

METHOD AND APPARATUS FOR CONSTRUCTING CONVERTIBLE TOP LINKAGES Filed May 15, 1967 I5 Sheets-Sheet 2 F164. FIG.5.

INVENTOR RAYMOND J. ALLDS ATTORNEYS Jan. 20, 1970 R. J. ALLDS 3,490,120

METHOD AND APPARATUS FOR CONSITUCTING CONVERTIBLE TOP LINKAGES Filed May 15, 1967 3 Sheets-Sheet v FIG.9.

INVENTOE RAYMOND J. ALLDS AT TOR NEYS United States Patent 3,490,120 METHOD AND APPARATUS FOR CONSTRUCTING CONVERTIBLE TOP LINKAGES Raymond J. Allds, Ashtabula, Ohio, assignor to The Ashtabula Bow Socket Company, Ashtabula, Ohio, a corporation of Ohio Filed May 15, 1967, Ser. No. 638,492 Int. Cl. B23p 17/04 US. Cl. 29-155 12 Claims ABSTRACT OF TIE DISCLOSURE This invention relates to a method and apparatus for deburring the rails, bows, and links of a convertible top framework so as to prevent tearing of the convertible top material and injury to passengers hands. The method includes the use of novel constant force opposed deburring rollers which act on opposite edges of the sheared sheet metal elongated blanks that are to form the framework elements. Pivoted arms support the rollers so that fluid driven pistons, such as by air-hydraulic boosters, acting through the arms can supply the constant force even as the width dimension of the elongated blanks varies. The mechanism to accomplish the action provides for a changing lateral movement of the piston which drives the arm to accommodate the are made by the pivoting arm during reciprocal movement of the piston.

In the production of convertible tops and in particular rails, bows and links for convertible top frameworks, it is customary to start from strip sheet steel and die shear various elements into planar blanks. These planar blanks are then dieformed to desired cross sections and assembled and fastened in interfitting relation to make the convertible top framework. After this operation has been completed, of course, the fabric top is added.

Automobile convertible tops have two basic stable conditions which are commonly called the top up position and the top down or crash position. Because of the metalworking and assembly procedures utilized in forming the framework elements from sheet steel stock and in particular because of the die shearing to shape which occurs, burrs or rough sharp and jagged edges are formed on the sheared edges of the metal which, when the convertible top is in the top up or enclosed position, present a danger to the hands and other extremities of the passengers and when the convertible top is in the top down or crash position tend to create tears and localized fatigue areas in the fabric of the convertible top.

Briefly, the present invention comprises a method of making a convertible top frame in which sheet metal strips are die sheared into elongated blanks having variable widths along their lengths. The blanks are fed between and in edgewise contact with opposed rollers of the apparatus which, because of its construction, can maintain a substantially constant force on the rollers to deburr their edges. The blanks, after being deburred, are die formed into the desired cross sectional configuration of the various frame elements and these elements are then assembled with the other necessary elements to form a convertible top frame. The apparatus has the opposed spaced rollers pivoted on arms having an opposite end portion which projects for a distance radially outwardly from the pivot point. A fluid driven reciprocating piston mounted in a cylinder housing acts on each of the arm ends to provide the constant force.

Accordingly, it is an object of the method and apparatus of this invention to provide a simplified and accurate method of removing burrs and rough edges created by the die shearing of the planar metal blanks which are to be "ice die-formed into rails, bows, and links of a convertible top framework.

It is a further object of the invention to provide an economical manner of providing edges which will present a safe and neat appearance and readily receive the metal finish and protective and decorative coatings and will not damage the fabric top.

These and other desirable objects will become more apparent upon a complete reading and understanding of the following description and drawings:

FIGURE 1 represents a convertible top framework and fabric combination in the crash position with a portion of the rear fender well shown in phantom for orientation purposes.

FIGURE 2 represents a typical cross sectional view of a convertible top framework rail.

FIGURE 3 illustrates the deburring apparatus constructed according to the principles of this invention in plan view.

FIGURE 4 is a cross sectional view along the line 44 of FIGURE 3.

FIGURE 5 is a cross sectional view along the line 5-5 of FIGURE 3.

FIGURE 6 is a side elevational view of the portion of the mechanism of FIGURE 3 taken along the line 66.

FIGURE 7 represents a perspective view of a typical die sheared blank before being die formed into the desired cross-sectional shape illustrated in FIG. 2.

FIGURES 8a through 8d are cross sectional elevational views taken along line 8-8 of FIG. 7 showing the progressive steps of burr removal accomplished by the method and apparatus of this invention.

FIGURE 9 is a schematic view of the constant force applying mechanism.

An automobile convertible top generally indicated by the numeral 10 is schematically illustrate din FIG. 1 and comprises basically: a fabric top 12 in a framework for supporting said fabric in both the closed or top up con dition and top down or crash position.

In the illustrated crash position, the framework is made of the front rail 14, the center rail 16 and a rear rail 18 with like parts on the opposite side of an automobile. A fender well 20 is illustrated in phantom for orientation of the device. The top 10 further includes a rear link 22, a center link 24, and a front link 26, which are connected respectively to like parts on the opposite side of the automobile by the rear bow 30, the center bow 32, and the front bow 34. Numerous links 36 supplement the main links previously mentioned in providing the necessary movement of the frame into and out of the two stable positions. A bracket 38 and a top header 40 make up the remainder of the major components of the convertible top in sufficient detail as will be seen.

The fabric 12 has a plurality of folds, such as the fold 42 between the center link 24 and the rear rail 18 and the rear link 22, such that it engages various edges of these elements. Since these elements are initially formed from strip steel by die shearing, if the burrs are not removed before assembly of the convertible top, when the top is in the crash position, folds of the fabric 12, such as shown at 42, become pinched and cut by the burred edges of the elements such as the links 24 and 22 and the rail 18.

To eliminate this cutting is one of the major purposes of this invention. The other major purpose is to eliminate the possibility of a passenger of the automobile being injured by a laceration or damage to the skin on the burr edges.

As shown in FIG. 2, a typical rail cross section illustrates the manner in which these edges are exposed, both to the fabric and to the passengers of the automobile. It will be seen that the edges 44 and 46 of the rail 18 in the position shown in FIG. 1 for example, open downwardly to permit movement of the center link 24 into the enclosure. In so doing, the fabric could come in contact to the edges 44 and 46 and be damaged or have abnormal Wear.

The novel apparatus of the invention is designed to prevent these major problems by providing an economical manner of deburring the edges of the elements before they are die formed into the shape of FIG. 2 from a flat planar die sheared blank, as illustrated in FIG. 3.

In FIG. 3, the deburring apparatus comprises a feeding mechanism generally designated by the numeral 48 and a deburring line generally designated by the numeral 50. The deburring line has work supporting rails 51 and 52 with opposed spaced rollers 54 and 55 located adjacent thereto on pivoted arms 56 and 57. A plurality of pairs of opposed rollers 54 and 55 and mounting means therefore and spaced along the work supports 51 and 52.

The roller support arms 56 and 57 are pivoted at points 60, as shown, and have extending outwardly therefrom pivoted arm portions 62 and 63 to which are rigidly connected gear segments 64. Shown in phantom on supports 51 and 52 is a work piece 18 which is a die sheared planar blank to be formed into a convertible top side rail or other similar metal component. Each gear segment 64 on the arm portion of the pivoted arms engages a similar segment 66 in a manner which is more clearly illustrated in FIG. 9.

The feed mechanism 48 comprises a conventional fluid driven reciprocating piston means 70 having a piston 71 with a work engaging member 72 for moving work pieces 18 into and through the roller deburring line 50 on the work supports 51 and 52. To avoid a bunching up of the material workpieces 18 as they are picked from the stack in the manner shown in FIG. 6 and moved against the preceding workpiece, work hold-down means 74 and 75 may be provided if desired, above the work support means 51 and 52.

The blank 18 as illustrated in FIG. 7, for example, thus enters the roller edge deburring line portion 50 from the feeding portion 48 of the apparatus having burred edges, as shown in FIG. 4 and finishes, because of the constant force application mechanism acting upon the pivoting arms 56 and 57, with smooth rounded deburred edges as illustrated, for example, in FIG. 5. Thus, the workpiece 18, as shown in perspective in FIG. 7, even though it varies in width along its length, because of the constant pressure applied to the edges by the rollers 54 and 55 begins with burred edges as shown in FIG. 8a, and progressively as it moves down the line and additional rollers contact it as shown in FIGS. 8b, 8c and 8d, is progressively deburred by a sWaging action due to the constant force being applied between the rollers.

The mechanism which applies the constant force to the pivoted arms 56 and 57, and consequently, to the rollers 54 and 55, is illustrated best in FIG. 9, wherein the cylinder housing 80 of an air-actuated hydraulic booster of conventional design is illustrated as being of a type which is readily available on the market and which is capable of converting shop air into a higher hydraulic pressure for operating hydraulic work cylinders.

The cylinder is made up of a housing 81 and a piston 82, with a piston 82 having a projecting arm extension which is pivotedly connected at a pivot point 84 to the arm portion 62 opposite the pivot point 60 from the arm 56 which supports a roller 54. As pressure of hydraulic fluid is applied at the point 85 and within the cylinder housing 81, the segment 66, which is pivotly connected to the housing 81 at pivot point 86 through its tooth engagement with the segment 64, because of its fixed pivot point 90, rotates in an arc of the same distance about the pivot point 90 as the segment 64 rotates about the pivot point 60. Thus, the cylinder housing 81 carried by the pivoting segment 66 likewise moves in an arcuate path as the piston 82 reciprocates Within the housing 81.

This action prevents a binding of the projecting shaft portion 83 against the housing 81 at the opening and permits the constant force to be applied hydraulically to the pivoting arm 56 and thus, to the roller 54. All of the rollers 54 and illustrated in FIG. 3 would, in the illustrated embodiment, have a connection to operate in this manner. It is through this novel mechanism that it is possible to accomplish the deburring with the constant force application so necessary to effectively eliminate burrs from the variously dimensioned planar blanks.

Thus, it will be seen that a novel method of deburring the rails, bows, and links of convertible top frameworks has been provided by means of the novel apparatus illustrated in the accompanying drawings.

It will be understood, of course, that modifications can be made in the preferred embodiments of the invention described and illustrated herein without departing from the scope and purview of the appended claims.

I claim:

1. A method of making a convertible top frame which comprises the steps of die shearing sheet metal strips to form elongated blanks having a variable width along its length, feeding the blanks between and in edgewise contact with opposed rollers while maintaining a substantially constant force on said rollers, die forming said blanks into the desired cross sectional configuration for the frame element to be formed and assembling said element with other elements to form the convertible top frame.

2. The method of claim 1 in which the step of maintaining a substantially constant force on said rollers includes the steps of pivoting arms upon which the rollers are mounted.

3. The method of claim 2 in which the step of pivoting the arms upon which the rollers are mounted includes the step of actuating fluid driven pistons mounted in cylinder housings and attached to said arms.

4. The method of claim 3 in which the step of actuating the fluid driven pistons includes the step of moving the cylinder housings laterally to accommodate the arc made by the pivoting arms during reciprocal movement of the pistons.

5. The method of claim 4 in which the step of moving the cylinder housings laterally is accomplished by move ment of the cylinder housings in arcs equal to the arcs travelled by the points at which the pistons act upon the pivoted arm portion.

6. The method of claim 5 in which the step of keeping the arcs equal is performed by pairs of rotating engaged pivoted gear segments with one segment of each pair pivotally attached to a cylinder housing and one segment rigidly attached to a pivoted arm end portion and pivotally attached to a piston extending from said housing.

7. A deburring apparatus comprising support means, opposed spaced rollers adjacent said support means, pivoted arms supporting each of said rollers adjacent and end thereof with the opposite end portion projecting for a distance radially outwardly from said pivot point, means acting on each of said arm end portions opposite said rollers to provide a constant force against opposite edges of a member in motion on said support means between said rollers even though the distance between said edges varies as said member is fed past said rollers.

8. The apparatus of claim 7 in which the means acting on each of said arm end portions is a fluid driven reciprocating piston mounted in a cylinder housing.

9. The apparatus of claim 8 in which the fluid driven reciprocating piston is pivotally attached to one of a pair of engaged pivoted segments, said one pivoted segment being rigidly attached to an arm end portion and the other of the pivoted segments of said pair is attached to the cylinder housing.

10. The apparatus of claim 9 in which each pair of segments is mounted such that the cylinder housing can References Cited move laterally in an arc equal to the arc travelled by the UNITED STATES PATENTS point at which said reciprocating piston acts upon the piv- 3,318,131 5/1967 Newman 72 245 arm 3,336,778 8/1967 Follrath 72-203 11. The apparatus of clalm 10 in which the cyhnder 5 3,406,439 10/1968 Hutchens 29 155 housing are supplied by hydraulic boosters which are air t t d, THOMAS H. EAGER, Primary Examiner 12. The apparatus of claim 7 in which the member in U S c1 X R motion on said support means is moved by a fluid driven 10 reciprocating piston means adjacent said support means. 29-434; 72203: 245 

